Thread: Abt Views in Sql

I know views can be updated when it is based on a single base table.And views cannot be updated when there r more than one Base table.If a view uses a group function in it is it updatable.And what r there any conditions for updating a view

In order to update a view which joins two or more table you can use INSTEAD OF trigger if possible.

This link might help you in this regard http://www.jlcomp.demon.co.uk/faq/joinview.html

Thanks a lot james i found the link useful.

moreover views which are using group by functions are not updatable. It is bviouse you don't have a records reference and each record in these views actually referring multiple records of the source table.

A join view can't be updated if it contains
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1.hierarchical query clause start with & connect by
2.group by & order by.
3.model query.
4.set operations.
5.aggragate functions .
6.a subquery or a collection expresion in the select list.
7.the distinct operator 8.the rownum pseudo column 9.read only option.